The primary goal of our research programs is directed towards an understanding of cell wall biosynthesis on the molecular level. A major emphasis is placed on the role of the membrane in this process. Knowledge of the membrane-associated enzymes and carriers that are involved in the synthesis of this macromolecular net will be integrated with the control systems that govern the synthesis, assembly, and amplification of this structure. In directing our goals for the project period, areas of research will include the translocation of precursors, regulation of peptidoglycan synthesis, specificity of glycan synthesis, development of new probes for polymer synthesis and synthesis of membrane teichoic acid. Seven specific projects will be investigated. 1. Design of analogues of D-alanyl-D-alanine that are potential antibacterial agents. 2. Effect of steric substituents in residue 4 on the activity catalyzed by DD-carboxy-peptidase. 3. Incorporation of residue 4 substituents into peptidoglycan of E. coli W. 4. Lipophilic intermediates in membrane teichoic acid biosynthesis. 5. Intramolecular translocation of lipid intermediates in peptidoglycan synthesis studied with fluorescent probes. 6. Biosynthesis of spin-labeled peptidoglycan: the labeled polymer as a lysozyme substrate and as a tool to study membrane-glycan interaction. 7. Synthesis of spin-labeled penicillin and its use as a specific labeling reagent. An investigation of these seven projects will contribute to our understanding of cell wall assembly and membrane chemistry that relates to this process. Our present objectives will provide insights into the events, regulations, and translocations that occur in the bacterial membrane for elaboration of this extracellular structure, the cell wall.